Water Testing Lab

Several parameters help to determine water quality

The concentration of chloride ions is quite low in natural water systems. It increases in contaminated water. Moreover, high concentration of chloride ions makes the water salty and corrodes pipelines of water.

The decomposition of organic matter like protein, amino acid increases the concentration of Ammonia in water.  Besides, it also increases with the use of chloramine in the water disinfection process. Concentration of NH3 in ground water systems is usually 3mg/ltr. If its concentration is greater than 50mg/ltr, it gives characteristic taste and odor.

• It is a very unstable intermediate formed during conversion of NH2 into nitrate.
• In aerobic condition nitrite is oxidized into nitrate whereas in anaerobic condition, nitrite is reduced to ammonia.
• If the concentration of nitrite is greater in drinking water, it brings serious health hazards to the consumers.
• Disease caused by high concentration of nitrite in infants is called Blue baby syndrome, which is characterized by blue coloration of skin
• Level of nitrite in drinking water should not exceed 3mg/ltr.
• **Note; blue baby syndrome: hemoglobin has greater affinity for nitrite than oxygen. Therefore, if the level of nitrite is high in blood due to consumption of contaminated water then it inhibits formation of oxyhemoglobin, instead it forms nitrosomyoglobin. This prevents transport of Oxygen to tissue giving characteristic blue color. In infants nitrite poisoning occurs even due to high concentration of nitrate in drinking water because the stomach of the infant is less acidic. In this situation nitrate is reduced by intestinal bacteria into nitrite causing blue baby syndrome.

• It is the most stable oxidized form of nitrogen. In water nitrate comes from organic matter decomposition and from atmospheric nitrogen fixation.
• Like nitrite Nitrate should not exceed 3mg/ltr in drinking water. It is because nitrate can be reduced into nitrite in the gut of infants and causes nitrite poisoning.
• Nitrate is very important in natural water systems like lakes and ponds because high concentration of nitrate facilitates heavy growth of aquatic plants causing eutrophication.

• In water phosphate is present in the form of H2PO4-, polyphosphate and as organic phosphate.
• Phosphate in water sources comes from agricultural wastes, sewage and from industrial effluent.
• Phosphate is not toxic to human beings but it is an important chemical in natural water systems like ponds because its high concentration facilitates eutrophication.

• Hardness of water is merely due to salt of calcium and magnesium.
• Temporary hardness is due to carbonate and bicarbonate of calcium and magnesium while permanent hardness is due to chloride and sulfate of calcium and magnesium.
• Water is classified as 9on the basis of concentration of calcium carbonate)
  • Soft water:<5omg/ltr
  • Moderately hard water: 50-150 mg/ltr
  • Hard water: 150-300 mg/ltr
  • Very hard water:>300 mg/dl
• Hard water is not suitable for industrial use. But hard water is usually beneficial for drinking purposes. However, hardness caused by MgSO4 gives some serious health effects. So, the concentration of Mg++ should not exceed 50 mg/lt in drinking water.